Can tornadoes jump?
Photo: Flickr user FloraG
Sometimes tornadoes look like they jump. What causes this?
Tornadoes don’t actually jump – a tornado is really always in contact with the ground. When you think of a tornado, you probably imagine a huge funnel cloud, but that funnel cloud and its tornado are slightly different. A tornado is a violently rotating column of air that extends from a thunderstorm to the ground. Inside a tornado, a funnel-shaped cloud sometimes becomes visible. The visible cloud forms because the air flowing into the tornado has water vapor in it. Tornadoes can look like they’re jumping, because the funnel cloud that’s inside the tornado may rise up off the ground in response to variations in air pressure and wind speed. Visible funnel cloud or not, a tornado can be destructive. Its winds at ground level can reach 500 kilometers – or 300 miles – an hour.
It may also seem that a tornado has jumped because of the irregular damage patterns it has left behind. That happens because, inside a tornado, you can have several different subvortices – smaller, rotating columns of wind – that whirl around each other. Each of these columns of wind can cut separate paths. Variations in wind speed, caused by different features of the terrain, are another reason tornado damage can vary from place to place. And finally, the construction of buildings themselves plays a large part in their ability to withstand a tornado.
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